Elastin is the main protein of the elastic fiber found in various vertebrate tissues. The hydration level in this mainly hydrophobic protein is known to play an important role in its structure and function. Many diseases of various tissues, such as the heart, have been shown to be correlated to structural degradation of elastin. The broad objective of the proposed research effort is to investigate the role of water in the structure and function of elastin using novel strong pulse gradient q-space Nuclear Magnetic Resonance (NMR) imaging, spin counting NMR and deuterium double quantum filtered NMR studies. Q-space imaging is a well known scheme for measuring the probability of molecular displacement in a sample. This technique was successfully implemented in the previously funded project to measure the average surface- to-volume ratio of pores in elastin fibers. The technique will extended to measuring the surface tension of water confined in pores of elastin by mechanically stressing a sample. Double Quantum Filtered NMR on deuterium- hydrated elastin samples will further probe local anisotropic motion within elastin using a well defined NMR radiofrequency pulse sequence. NMR spin counting experiments will be used to measure the average number of nuclear spins that are clustered in the waters of hydration surrounding elastin due to the presence of a partially averaged dipolar interaction. The experimental findings of this study will be used to test and develop models of elastin, and the role of water in its function. The materials and methods necessary for this study draw upon pulse sequences well-known in the NMR community, as well as hardware that was built in the previously funded stage. The PI of the effort has a significant amount of experience in such experimental work from graduate studies, postdoctoral work and from his first two years as a junior faculty member at York College. The experiments will make use of two already existing NMR magnets and spectrometers with solid- state capabilities that are available on the college campus. PROJECT NARRATIVE This research effort seeks to investigate fundamental knowledge about the nature and behavior of elastin, a biopolymer that that confers elasticity to many vertebrate tissues. The elasticity of this biopolymer is known to be correlated to hydration, and the aim of the effort is to characterize the dynamics of water in the biopolymer. The proposal fits well within the overall goals of the National Institute of Health for fundamental research into the nature and behavior of living systems for extending healthy life and reducing the burdens of illness and disability.